“You’re Laughing” Means You’re in a Good Position

In everyday Australian speech, you’re laughing can mean that you are now in a favourable position and have little left to worry about. It does not necessarily describe actual laughter. Cambridge defines be laughing as having circumstances that make a situation easy or advantageous.

A: Is the walk difficult?
B: Once you’re past the steep first kilometre, you’re laughing.

The point is that, after the hardest section, the rest should be manageable. The phrase is informal and also occurs in British English, so it is not uniquely Australian. Do not confuse it with you’re having a laugh, which often means that someone’s suggestion is unreasonable. In a more formal context, say You should be fine from there.

https://dictionary.cambridge.org/dictionary/english/be-laughing